Fever after costal cartilage harvesting during reconstructive surgery in pediatric patients for microtia; validation of fever using rat model

In general, body temperature decreases during anesthesia. However, we found that body tem-perature increased during reconstructive surgery for microtia involving autogenous costal car-tilage harvesting. Therefore, we aimed to compare changes in body temperature and cytokine concentrations between two types of simulation surgery (embedding and elevation) using rat models. Two simulation surgeries were performed on male Sprague-Dawley rats (8 weeks old, n=25). The 8th and 9th costal cartilages (1-1.5 cm long) were harvested in the first operation, but not in the second. We compared changes in body temperature, interleukin-6 (IL-6) levels, and tumor necrosis factor-alpha (TNF-a) concentrations between the first and second opera-tions. Body temperatures increased in the costal cartilage harvest group compared with another group. Body temperature changes between the two groups were statistically significant at 5 to 6 h after anesthesia in rats (p<0.05). However, IL-6 and TNF-a levels were not significantly dif-ferent between the two rat groups. As a result of this study, it was confirmed that the harvesting costal cartilage increased the body temperatures of rats during surgery. However, there were no significant differences in cytokine concentrations. Further research is required in the future to determine the cause.